Knotless anchor for surgical repair

ABSTRACT

Knotless fixation of soft tissue to bone is accomplished using a bone anchor configured to provide interference fixation of a soft-tissue connector. The soft-tissue connector is provided in the form of a flat narrow piece of material. Additional fixation strength can be provided by configuring the bone anchor to penetrate into or through the soft-tissue connector. The bone anchor is installed into a pre-formed hole or socket in the bone.

This application claims the benefit of U.S. Provisional Appl. No.60/580,349 filed Jun. 18, 2004, the disclosure of which is incorporatedherein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to apparatus and methods for tissuerepair, and more particularly to techniques using knotless anchors forfixation of soft tissue to bone.

2. Description of the Related Art

When tissue structures such as tendons or ligaments (“soft” tissues),detach from bone-tissue structures (“hard” tissue), it may becomenecessary to reconnect the structures surgically. Techniques and devicesthat have been developed generally involve knotting suture to anchor thesoft tissue to the hard tissue. Reattachment with suture, and theknot-tying involved, can present significant difficulties. Operating inthe shoulder joint space, for example, particularly arthroscopicsurgery, can be very challenging. It would be beneficial tosurgically-anchor tissue torn from bone without the need to tie knots insuture.

Knotless methods and apparatus for attachment of soft and hard tissuestructures are disclosed in U.S. Pat. No. 6,544,281 to ElAttrache et al,the entire disclosure of which is incorporated herein by reference.ElAttrache et al. discloses securing soft tissue to bone using lengthsof suture thread. The suture thread is secured in a pre-formed socketwith an anchor without the need for tying knots. The suture threads areheld in place on the end of an inserter/driver using a loop of suture orby inserting ends of the suture into a distal cannula of theinserter/driver. Management of suture threads in certain surgicalsituations can be difficult and cumbersome. The need exists forsimplified knotless anchoring apparatus and techniques that also providebroader surgical application and improved fixation strength.

BRIEF SUMMARY OF THE INVENTION

The present invention includes soft-tissue connectors, anchoring devices(anchors), instrumentation, and related surgical techniques andconstructs used to secure suture to bone without the need to tie a knotin suture. An exemplary soft-tissue connector is provided in the form ofa flat, narrow tape material. The tape material can be formed of suturecan be configured as a webbing which is manufactured by weaving orbraiding. Additionally, the soft-tissue connector can be a syntheticmaterial for which weaving or braiding is not required. Furtheralternative types of soft-tissue connectors can include, withoutlimitation, a portion or extension of the ligament, graft, or softtissue to be fixed to bone.

The soft-tissue connector is attached to soft tissue and secured to boneusing an anchoring device. The anchoring device is used to hold thesoft-tissue connector in a pre-formed socket by interference fixation.

In one exemplary form, the anchoring device has a cannulated body. Thecannula, formed axially through the anchor body, serves severalpurposes. The cannula receives an anchor driver and/or a soft-tissueconnector holding device during installation. Additional anchoringfixation can be provided by a pin driven into tissue through thecannula. The anchor driver also can be cannulated to fit over a guidewire during installation.

The invention can be used for various reattachment purposes, includingbiceps tendon and rotator cuff. In an exemplary application, rotatorcuff repair proceeds in the shoulder by attaching a length ofsoft-tissue connector to the rotator cuff. At least one limb of thesoft-tissue connector extends from the attachment point on the rotatorcuff. At least one pre-formed hole or socket is provided at thearticular margin of the shoulder. A driver is fitted with the anchor anda guide wire. The point of the guide wire protrudes a few millimetersfrom the tip of the driver.

The limb of soft-tissue connector is extended across the pre-formedhole, and a length of the soft-tissue connector is urged into thepre-drilled socket to form a U-shaped open loop with the soft-tissueconnector limb. The soft-tissue connector, preferably provided in theform of a flat, woven tape, extends generally down one side of thesocket, across the bottom, and back up the other side. The length ofsoft-tissue connector required is adjusted so that the attached tissueis approximated toward the pre-drilled hole, adjacent the opening-edge.Instruments are provided for holding the appropriate length ofsoft-tissue connector in the socket prior to fixation with an anchor.With the soft-tissue connector limb held in place, the anchor is driveninto the pre-drilled socket until the drive-end is flush with the outersurface of the surrounding bone.

Once the anchor is installed, the anchor driver is removed. The guidewire can be left in place. A cannulated pin is loaded onto the guidewire and driven into and through the cannulation of the anchor until thecannulated pin is flush with the surface of the surrounding bone. Thecannulated pin pierces the soft-tissue connector to enhance fixation.The construct preferably rigidly secures a fixed length of soft-tissueconnector to bone. Exposed extraneous soft-tissue connector is cut offflush to the bone surface.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view depicting an initial step in a method ofrotator cuff repair according to the present invention;

FIG. 2 is a perspective view depicting a next step in a method ofrotator cuff repair according to the present invention;

FIG. 3 is another perspective view depicting a further step in themethod of rotator cuff repair subsequent to the step shown in FIG. 2;

FIG. 4 is another perspective view depicting a further step in themethod of rotator cuff repair subsequent to the steps shown in FIGS.1-3, in which a cannulated pin is loaded onto a guide wire;

FIG. 5 is an enlarged perspective view depicting a concluding step inthe method of rotator cuff repair subsequent to the steps shown in FIGS.1-4, in which the cannulated pin has been installed and excesssoft-tissue connector is cut off;

FIG. 6 illustrates use of an alternative anchoring device having apointed tip or sharp spike for engaging soft-tissue connector bypenetrating the tape and preventing slip;

FIG. 7 illustrates use of an anchoring device and soft-tissue connectorwith reinforced perforations according to an alternative embodiment ofthe invention;

FIG. 8 illustrates use of a single-limb construct according to analternative embodiment of the invention;

FIG. 9 illustrates an alternative development of a single-limb constructaccording to an alternative embodiment of the invention; and

FIG. 10 illustrates use of a single-limb construct for double-rowfixation according to another exemplification of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring initially to FIG. 1, repair of a torn rotator cuff 2 proceedsby passing a length of soft-tissue connector 4 through the detachedportion of the rotator cuff 2. An exemplary soft-tissue connector 4 ismarketed as Fibertape™ by Arthrex, Inc., Naples, Fla. A pre-formedsocket 6 is created at the articular margin of the shoulder. The socketcan be formed by drilling or core removal, for example.

Referring to FIG. 2, an anchor driver 8 is fitted with a cannulatedthreaded anchor 10 disposed over a guide wire 12. Anchor 10 also isreceived over an inner shaft 13 of driver 8. The inner shaft 13 isremovable from within the driver 8 and can be advanced independently ofdriver 8. The tip of the guide wire 12 protrudes a few millimeters fromthe tip of the inner shaft 13 of driver 8. Two limbs of soft-tissueconnector 4 are overlapped across the opening of the socket 6.

Referring to FIG. 3, the exposed tip of guide wire 12 and the tip ofinner shaft 13 are used to engage and urge the overlapped limbs ofsoft-tissue connector 4 into the bottom of the pre-formed socket 6. Thelength of soft-tissue connector urged into the socket is judged andadjusted so that the rotator cuff 2 is approximated to the preformedsocket 6. With the soft-tissue connector held in place within thesocket, the threaded anchor 10 is advanced over the guide wire anddriven in until flush with the surface of the surrounding bone.

Referring to FIG. 4, once threaded anchor 10 is installed into socket 6,anchor driver 8 is removed, leaving guide wire 12 in place. A cannulatedpin 14 is loaded onto guide wire 12. Cannulated pin 14 is advanced alongthe guide wire 12 and driven into the cannulation of threaded anchor 10.The cannulated pin 14 is urged flush with the surface of the surroundingbone. Preferably, the tip of cannulated pin 14 extends beyond the end ofcannulated bone anchor 10 and penetrates into or through soft-tissueconnector 4 to enhance securement within bone socket 6.

Referring to FIG. 5, the reattachment is finished by trimming off theexposed ends of soft-tissue connector 4 to be flush as possible with thesurrounding bone. The steps above can be repeated to provide anadditional anchor fixation point as indicated. Further, the presentinvention is not limited to using only one length of soft-tissueconnector, but includes securement of additional soft-tissue connectorswith one bone anchor, for example.

FIG. 6 illustrates an alternative embodiment of the present invention inwhich a pointed-tip anchor 20 used in a method similar to that describedabove in connection with FIGS. 1-5. Pointed tip 22 of anchor 20 engagessoft-tissue connector 4 at the bottom of socket 6. Anchor 20 can becannulated or solid.

Referring to FIG. 7, a perforated soft-tissue connector 24 can be usedin place of soft-tissue connector 4. Perforated soft-tissue connector 24features perforations 26. In the double-limb construct shown in FIG. 7,an anchor 30 has a shaped tip that is inserted through two alignedperforations 26. A driver 32 is used to install the anchor 30 and thecaptured soft-tissue connector 24 into socket 6.

FIG. 8 illustrates a single-limb construct according anotherexemplification of the present invention. A length of a soft-tissueconnector 34 is passed through rotator cuff 2 and then through itselfusing a suture needle, for example, to form a loop. The procedure iscarried out in a similar fashion to that described above in connectionwith FIGS. 1-5. An alternative single-limb construct is shown in FIG. 9in which soft-tissue connector 34 is provided with an eye 36. Thesingle-limb of soft-tissue connector 34 can be simpler to engage andpenetrate than a double-limb.

FIG. 10 illustrates a single-limb construct used in double-row fixationaccording to another exemplification of the present invention. A medialsocket 40 is prepared and a bone anchor 42 secures a length ofsoft-tissue connector 41 to the bone. The bone anchor 42 may have an eye43 to which the soft-tissue connector 41 is secured. A lateral socket 44is formed, and a length of the soft-tissue connector 41 is passedthrough the rotator cuff 2. The soft-tissue connector 41 is secured insocket 44 using an anchor/driver assembly 46 including an anchoringdevice similar to those described above. The anchor/driver assembly alsocan be configured similar to that shown and discussed, for example, inconnection with FIGS. 7-11 of U.S. Pat. No. 6,544,281 to ElAttrache etal., discussed above and incorporated herein by reference.

Each of the anchor configurations noted above can be provided in ascrew-in or press-in configuration. In a press-in configuration, theanchor can be installed by impact pressure, using a slap-hammer, forexample. Alternatively, the anchor can be pressed in with gradualapplication of pressure. Various bone anchor configurations andinstallation techniques that are known to those of skill in the art,adapted to engage and secure soft-tissue connector as described herein,can be used without limitation in connection with the present invention.

Although the present invention has been described in connection withpreferred embodiments, many modifications and variations will becomeapparent to those skilled in the art. The present invention is to belimited not by the specific disclosure herein, but only by the appendedclaims.

1. Surgical apparatus comprising a bone anchor configured at a distalend to penetrate a soft-tissue connector.
 2. Surgical apparatus as inclaim 1, wherein the bone anchor has a spiked distal end.
 3. Surgicalapparatus as in claim 1, wherein the bone anchor is cannulated, andfurther comprises a pin arranged to be advanced in the cannulated boneanchor to penetrate the soft-tissue connector.
 4. Surgical apparatus asin claim 3, wherein the pin is arranged such that a forward end of thepin penetrates through the soft-tissue connector.
 5. Surgical apparatusas in claim 1, further comprising a driver.
 6. Surgical apparatus as inclaim 5, wherein the anchor and the driver are cannulated and advanceover a guide wire.
 7. Surgical apparatus as in claim 6, furthercomprising a cannulated pin configured to advance over the guide wireand into the anchor cannulation.
 8. Surgical apparatus as in claim 1,wherein the bone anchor is threaded.
 9. A surgical method comprising:forming a socket in bone; extending a connector attached to soft tissueto form at least one connector limb; and securing the at least oneconnector limb within the socket by interference fixation.
 10. Asurgical method as in claim 9, wherein the step of extending a connectorattached to soft tissue comprises looping a flat narrow soft-tissueconnector through soft tissue.
 11. A surgical method as in claim 9,wherein the step of securing the at least one connector limb comprisesinstalling a bone anchor in the socket.
 12. A surgical method as inclaim 11, wherein the bone anchor is cannulated, the method furthercomprising holding the connector limb in the socket while installing thebone anchor into the socket.
 13. A surgical method as in claim 12,wherein the cannulated bone anchor is threaded, and is driven into thebone socket by rotation.
 14. A surgical construct comprising: a socketformed in bone; a length of a soft-tissue connector attached to tissueand extended to form at least one limb of the soft-tissue connector; andan anchor arranged for interference-fixation of the limb of thesoft-tissue connector against inner surfaces of the socket.
 15. Asurgical construct as in claim 14, wherein the soft-tissue connector isformed as a flat, narrow material.
 16. A surgical construct as in claim14, wherein the anchor is cannulated.
 17. A surgical construct as inclaim 16, further comprising a pin configured to be received securelywithin the cannulated anchor and penetrate the soft-tissue connector.18. A surgical construct as in claim 17, wherein the pin is configuredto penetrate through the soft-tissue connector.